1. Field of the Invention
The present invention relates generally to service stations for ink-jet printers and more particularly to such service stations which can be utilized to service either a color pen or a black pen, whichever is installed in the printer.
2. Description of the Related Art
An ink-jet printer includes a replaceable printing cartridge or pen having a printhead formed thereon. The cartridge includes a reservoir of ink which is fired through nozzles in the printhead onto a printing medium such as paper. The structure and operation of such printing cartridges is well-known to those skilled in the art.
Prior ink-jet printers include a service station at one end of the travel path of a printing carriage upon which the printing cartridge is mounted. The service station includes a wiper for wiping the printhead to remove contaminants, dried ink and the like from the printhead surface containing the nozzle openings. Also provided is a cap which covers the printhead when the printer is not printing to prevent the ink in the nozzles from drying. The service station may also include a spittoon into which ink from the nozzles can be fired to clear the nozzles of any viscous ink.
Most prior art ink-jet service stations include a wiper which is fixed on the service station with its tip slightly above the plane of travel of the pen surface. As the pen moves into the service position, it traverses the tip of the wiper thereby wiping the pen surface. Only one wipe is provided each time the pen moves into or out of the service position.
Some ink-jet printers are equipped to print with either black ink, when a black cartridge is installed, or in color ink, when a color cartridge is installed. Because of the differences in color and black cartridges, separate caps and wipers are used to cap and wipe each cartridge. Some prior art ink-jet printers are operable to receive either a black cartridge or a color cartridge and print according to which cartridge is installed. Such printers require a service station which can cap and wipe both types of cartridges. An example of such a service station is disclosed is U.S. Pat. No. 5,146,243 to English, et al for a diaphragm cap system for ink-jet printers, which is incorporated herein by reference. This prior art patent includes a rotatable service station having a color cap and wiper on one side thereof and a black cap and wiper disposed on an opposite side. Each cap is mounted on an associated sled which is loosely clipped onto the service station so as to be retained when the service station rotates 180 degrees to present the other wiper and cap to the print cartridge. Each sled is slidable laterally, parallel to the bidirectional path of the print cartridge, along a cam surface. As the print cartridge moves into the service station at one end of the cartridge travel path, it engages a post on the appropriate sled thereby dragging the sled along the cam surface which causes the same to be urged into capping engagement with the print cartridge.
While the foregoing system provides a very effective service station, it takes up more space than would ideally be used for a service station on a portable printer. It would be desirable to provide a compact service station for a portable printer.
It would be also desirable to provide such a service station which can service both color and black pens.
It would be further desirable to provide such a service station in which the capped position is locked to insure proper capping of the pen when the printer is transported.
It would also be desirable to provide such a printer in which pen wiping can be provided either passively, in response to a pen passing by a fixed wiper, or actively, in response to wiper movement relative to the pen.
It is also desirable to provide such a service station which produces an accurate capping force.
It is further desirable to provide such a service station which includes foam therein for directing ink away from electronic circuitry in the printer.